Sulfonamides Flashcards
what are sulfonamides structural analogues of
paramino benzoic acid
MOA of sulfonamides
suppress bacterial growth by inhibiting synthesis of folic acid (needed for DNA, RNA, and proteins)
are sulfonamides bacteriostatic or bacteriocidal
bacteriostatic
what is the principle indications for sulfonamides
UTIs and DOC for nocardiosis
MC sulfonamide that is used for UTIs
sulfamethoxazole in combo w/ trimethoprim
do sulfonamides cross the placenta
yes
where are sulfonamides metabolized
liver
MC side affect of sulfonamides
skin hypersensitivity reactions
most serious but rare hypersensitivity of sulfonamides
Steven Johnson’s Syndrome
what are sulfonamides chemically related to
thiazide & loop diuretics, sulfonylureas
what genetic deficiency should you not give sulfonamides to
G6PD (the drug can cause acute hemolytic anemia
what should you do if sulfonamides are used for a long time
periodic blood tests
what fetal effects can sulfonamides have when a child is born
kernicterus (disposition of bilirubin in the brain causing severe neurologic deficits and even death)
what can happen is you use older sulfonamides
renal damage from crystalluria
drug interactions of sulfonamides
warfarin, phenytoin, sulfonylurea type oral hypoglycemics
examples of systemic sulfonamides
Sulfisoxazole (Gansitrin)
Sulfamethoxazole (Gantanol, Urobak)
Sulfadiazine
examples of topical sulfonamides
Sulfacetamide (Bleph-10)- widely used for conjunctivitis,
corneal ulcer
Silver Sulfadiazine (Silvadene) & Mafenide (Sulfamylon)Trimethoprim MOA
interferes with production of tetrahydrofolic acid suppressing DNA, RNA, and proteins
antimicorbial spectrum of trimethoprim
most enteric G- (e coli, kelbsiella pneumoniae, proteus mirabilis, serratia marcesans, salmonella, shigella
some G+
some Protozoa
therapeutic use for trimethoprim
initial therapy for acute, uncomplicated UTI
some adverse effects of trimethoprim
hematologic (usually in people w/ existing folate deficient)-
megaloblastic anemia, thrombocytopenia,
neutropenia
hyperkalemia
caution in breast feeding
trimethprim-sulfamethoxazole (Sepra, Bactrim) narrow or broad spectrum
broad
uses for Bactrim/Sepra
UTIs (great for chronic or recurrent infections)
DOC for Penumocystitis Pneumonia (PCP)
GI infections from G- bacilli
OM & acute exacerbations of chronic bronchitis
Whooping cough, nocardiois, brucellosis, meloidiosis, listeriosis, chancroid
does bactrim/sepra cross the placenta/ breast milk
yes
drug interactions of Bactrim/sepra
same as sulfonamides (warfarin, phenytoin, sulfonylurea type oral hypoglycemics)
